This invention relates to electronic thermometers. More particularly, the invention relates to the absolute value precision adjustment of an electronic thermometer.
It is known, in electronic thermometers in which a thermosensing element and a reference resistor are used, to improve the accuracy of the temperature measurement by providing for adjustment of the absolute value of the reference resistance relative to the thermosensing element at the time of the adjustment. To this end, the reference resistor is connected in series with a variable resistor and the difference between the resistance of the thermosensing element and that of the reference is compensated for by adjusting the variable resistor.
In thermometers of the type just described, the compensating adjustments take a long time to complete, the realization of a highly precise, absolute value adjustment is difficult, and, because of the the required expensive variable resistor and the many steps required in manufacturing, the electronic thermometer is costly.